1. Technical Field
The present invention relates to: an oil-impregnated bushing made of a metal sintered body impregnated with lubricating oil; an oil-free chain, which is to be used for a power transmission mechanism, a conveyance mechanism and the like and is constructed in a manner such that an oil-impregnated bushing and a pin are in sliding contact with each other in a state where the lubricating oil for impregnation of the oil-impregnated bushing oozes out without additional lubrication; and a method for manufacturing an oil-impregnated bushing.
2. Description of Related Art
Conventionally, a chain such as a bushing chain or a roller chain has been used as a power transmission mechanism and a conveyance mechanism. A bushing chain is constructed by connecting a pair of inner link plates which have both end parts connected by two bushings (bearing bushing), and a pair of outer link plates which are connected by two pins inserted into adjacent bushings of two pairs of inner link plates, alternately. In the case of a roller chain, rollers fitted on bushings are further provided.
An oil-free chain, which uses an oil-impregnated bushing made of a sintered body impregnated with lubricating oil as a bushing for a chain having the structure described above and is constructed in a manner such that the oil-impregnated bushing and a pin are in sliding contact with each other in a state where the lubricating oil for impregnation of the oil-impregnated bushing oozes out without additional lubrication, is known.
Japanese Patent Application Laid-Open No. 2004-286115 discloses an invention of an oil-free chain obtained by impregnating a bushing with fluorine-binding oil having a straight-chain structure or a side-chain structure.